1. Field of the Invention
The present invention relates to a substrate treating apparatus and a substrate treating method for supplying a treatment liquid to a semiconductor substrate, a glass substrate for liquid crystal display, a glass substrate for photomask, an optical disk substrate, and the like (hereinafter, simply referred to as a “substrate”). More particularly, the present invention is directed to a technique of a cup for collecting the treatment liquid.
2. Description of the Related Art
Japanese Unexamined Patent Publication 2014-75575A discloses a substrate treating apparatus. The substrate treating apparatus includes a substrate holder, a rotary drive mechanism, first and second nozzles, a cup body, first and second drain ducts, an exhaust duct, and a movable cup. The substrate holder holds the substrate horizontally. The rotary drive mechanism rotates the substrate holder. The first nozzle supplies developer for positive tone development. The second nozzle supplies developer for negative tone development. The cup body collects the developer. The first and second drain ducts and the exhaust duct are each connected to the cup body. The movable cup moves upward and downward, thereby guiding the developer to either the first drain duct or the second drain duct.
For instance, when the first nozzle supplies developer, the movable cup guides the developer to the first drain duct. When the second nozzle supplies developer, the movable cup guides the developer to the second drain duct. The first drain duct drains the developer for positive tone development, whereas the second drain duct drains the developer for negative tone development. At this time, the exhaust duct exhausts gas within the cup body (in this case, the gas with mist in the developer). Accordingly, this prevents the developer for positive tone development and the developer for negative tone development to be mixed in the first and second drain ducts. The exhaust ducts each exhaust the gas within the cup body (containing the mist in the developer) when the first and second nozzles supply the developer, respectively.
However, the example of the conventional apparatus with such a configuration has the following drawback. That is, the exhaust duct exhausts both the mist of the developer for positive tone development and the mist of the developer for negative tone development. Consequently, the different types of mist of the developer may be mixed in the exhaust duct. When the different types of mist of the developer are mixed, this may cause difficulty in keeping a clean atmosphere within the cup, and thus also may cause difficulty in high-quality substrate treatment.